Appliance for determining the hardness of materials



P. V. VERNON.

APPLIANCE FOR DETERMINING THE HARDNEss o'F MATERIALS.

APPLICTION FILED MAR 17,1920.

INVENTU @54M aga@ P. Vl VERNON.

APPLIANCE FORDETERMINING THE HARDNESS OF MATERIALS. APPLICATION FILED MAR 17. i920.

1,369,993, Patented Mar. 1, 1921.

` 5 SHEETS-SHEET 2- www ATTORNEY l P. V. VERNON.

APPLlANc Fon ommmm; THE HARDNESS oF MATERIALS.

APPLICATION FILED MAR 17' 1920.

1,369,993. y I PatenaMar. 1,1921.

5 SHEETS-SHEET 3- vHKU/EN TOR PER A TTORNEY P. V. VERNON. APPLIANCE FOR DETERMINING THE HARDNESS 0F MATERIALS.

APPLICATION F| LED MAR 17| 1920.

Patented Mar. 1,- 1921.

5 SHEETS-SHEET 4.

y v [NYENTDR Ek? Z//h Qing/@hlm FIGS ATTORNEY P. V. VERNON.

APPLIANCE FOR. DETERMINING THE H'ARDNESS 0F MATERIALS. APPLICATION FILI-:D MAR I7. I92o'l 1,369,993. Patented Mar. 1,1921.

5 SHEETS-SHEET 5.

v APPLIANCE FOR DETERMINING: THETIARDNESS F MATERIALS.

ieaeas.

Specication of Letters Patent.

. Application filed March 17; 1920. Serial No. 866,523.-

. the kind in which an indentation is made in the surface of the test-material by the agency of an indenting tool such as a hardened ball or' the like of a definite size or form and acted upon by `a definite loadpressure.

'It is known that with such a testing appliance, the consistency and value of the results is primarily dependent upon the time element in both the attainment from zero of the load and the duration of its application at'its maximum value. The present invention has for its principal object to in-5 sure that suchconditions are satisfied and that they are reproduced in a similar manner for each specimen tested.

Further objectsare to provide an appliance which can be operated with accuracy and considerable rapidity so that tests can be made in quick succession, and without undue fatigue to the operator, and to ar-, range it so that no load-compensations or l adjustmentsare required for test-pieces of varying weight or size.

According 'to this invention, the testspecimen and the indenting means, acting against a substantially constant loady device (such as a resilient-thrust member or like device constituted by a weight or a weighing machine), are thrust together by means,

such as a cam, actuated by a shaft rotating at a constant speed and adapted to actso that in predetermined intervals of time,the load is applied, sustained, and withdrawn.

Preferably the load-weighing (or yielding thrust member), and the load-applying means are entirely independent of one another and act on opposite sides of the testspecimen, the former above it, and the latter below it, means being provided for adjusting the specimen in contact with the in-v denting means, before applying the load. Means are also combined with the foregoing parts whereby after starting veach test the cam or other operative device is automatically brought4 to rest after it has completed its cycle of operations.

Thel manner of carrying out this invention 1s illustratedy in th'e accompanying drawings, in which- A I Figure l'is a side elevation of the complete testing machine, parts of which are shown in vsection on a central plane.

Fig. 2 is a sectional front elevation on' thev line 2.2. of F ig. 1.

Fig. 3, toa larger scale than the foregolng 1s a part sectional side elevation of the portion ofthe appliance carrying the 'resilient thrust member, and

Fig. 4 is a view of Fig. 3 as seen inthe direction of the arrow X, while Fig. 5 shows a modified indenting device. i

Fig 6 illustrates in full lines the mechamsm shown in dotted lines in Fig. 1.

Like letters indicate like parts throughout the drawings.' y

-The bed A of the testinlr appliance carries a vertically movable rain constituting the load-applying member, through which extends lengthwise an adjustable pillar B2 provided with an external screw thread B3 adapted to take the full load thrust'. On the upper end of the pillar B2 is an anvil or table B*1 for the support of the test-specimen, and a nut B5 carried bythe plunger B .and lrotatable by means of a hand wheel Be engages the thread B3 on the pillar and thus .Patented Mar. il, 11921.

provides for adjusting the vertical height of the anvil, the pillar B2 being prevented from rotating by means of'a feather (not shown) in the ram B, engaging a featherway BT.

Above the anvil B4 is a vertically sliding plunger C constituting a resilient thrust member, in the lower end of which is provided a seating for the usual hardened steel ba-ll C2 of the known diameter, or any other type of indenting device. A screw cap C through which the ball C2 protrudes, serves to hold the latter upon its seating.

Thsplunger C is mounted in the free end rofa hollow arm A3 extending from a hollow i I standard A2 integral with the base A of the appliance.

The weight of the plunger C is sustained normally by means of a light spring C3, (for which a balance weight could be substituted if required), thereby holding it up against the operative part of a lever D which is so loaded as to resist upward movement of the plunger withv a force of sub'- stantially constant magnitude. This lever is mounted within the hollow arm A3 and eX- tends from the fixed part of it and through a slot C4 in the plunger to lthe fulcrum pins D2. v

For convenience, the latter are carried by a member D5 attached to the lever D, and are mounted in antifriction bearings D4 supported in the arm A2. A hardened steel roller D5 bearing upon appropriately hardened surfaces D6 is interposed between the co-acting faces ofthe plunger C and the lever D. At the free end-of the lever` D is a toothed portion D0 which isconcentric with the axis of the fulcru'm D2, and engaging these teeth is a pinion E fast upon a horizontally disposed shaft E2 By means of pulleys Es on the shaft E2, weights E4 con.- nected by a cord E5 to the rims of the pnlleys E2; offer a substantially constant resistance to upward movement of the ball-carrying plunger C throughout the range of its operative movement. t

A stop D7 is provided to vlimit the down- L ward movement of the free part of the lever D, and thereby also the downward movement of the plunger C under the'action of the load weights E4.

For purposes of calibration andrfor use when the standard loading is changed (e. g. from 3000 killos. to 500 kilos), aA sliding weight D2 is provided upon the lever D.

A multiplying indicator is connected to the plunger C and is adapted to show clearly when the latter is at rest in its lowest position due to contact of the lever D with the speed. This is conveniently carried out bymeans of a reduction gear comprising a worm wheel F2 fast on the shaft F and a worm G2 on a shaft G which is itself driven through skew wheels G2, H2. The latter wheel H2 is fast on a shaft H carrying a belt pulley H2 operatively connected to the power source. Carried by the shaft F is a cam Fs which bears unon a cam roller B2 mounted on the lower endv of the ram B. This cam F2 has a contour which is adapted first to raise the ram B in a pre-determined interval of time, then to hold it sustained for the required period, and thereafter to allow it to descend, all in one revolution `of the said cam.

The arrangement and disposition of the mechanism for the last-mentioned purpose is as follows: The worm wheel G2 is loosely mounted upon the shaft G and has at one end-face, dogs G4. These are adapted to be engaged by the cooperating dogs G5 on a sliding clutch member G5 which, by means of a feather and featherway, (not shown), is rotationally fast on the shaft G. The sliding tclutch member G5 is actuated by means of an augularly movable fork G7 fast on a shaft G2. By the agency of a spring G2 which is carried by a casing inclosing the worm a-nd worm wheel G2, F2, and bears upon van arm G10 'fast on the fork carrying shaft G8, the sliding clutch member G6 tends always to be thrust out of engagement with the worm G2.

Fast upon theshaft F is a cam F4, the periphery of which is concentric with the shaft F, except only where a concave notch F5 is formed in it. In this notch iis adapted to lie, (when the shaft F and thus also the cam F2 'are at rest), a roller G12 carried upon an arm G11, also fast upon-the fork carrying shaft G2. The arrangement of these several parts is such thaty the cam roller B8 carried by the ram B rests on the base of its cam F5 when the roller G12 lies in the notch F5 of the cam F4, and is there held by the thrust of the aforementioned spring G5, which latter at the same time is holding theysliding clutch member Gi out of engagementwith the worm wheel G2.

A pedal J, situated at the side of the base A of the appliance, is by means of a link J2 operatively connected to an arm J3 fast on the fork-carrying shaft G2. When the pedal J is depressed by the attendant, the fork G7 is actuated to cause the sliding clutch mem ber to engage the worm G2 and thus to cause it to be set in motion by the constantly running shaft G. At the same time the roller G12 is withdrawn from the notch F5 in the cam F4, and the latter being now set in motion by the agency of the worm G2, bears on the roller G12 with its concentric periphery. The latter has a radius such that its action on the aforesaid roller holds the clutch member G6 in engagement with the Worm G2 againstthe action of the spring G9 without requiring sustained pressure on. the pedal J.

When the shaft F has made one complete revolution, during which thecam F3 has performed its several functions as above set forth, the notch F`5fis again brought opposite to the roller G12.- jThe latter, under the action of the spring G2, then enters the notch F5, permitting at the same time, and by the same agency, the movement of the sliding clutch member Ge out of engagement with the Worm G2 and therebybringing the shaft F and its cam F2 to rest. Thus it will be seen that after starting the test operations by actuating the pedal J, these are all performed mechanically and the operating parts are brought to rest again automatically at the conclusion of the test.

The indicating means, above mentioned, 180

which are adapted to show when', by vthe upward adjustment of the table or anvil B4, a test piece carried upon the anvil has'made contact with the indenting ball C2 and taken up any lost motion in its associated parts, are shown -clearly in Figs. 3 and 4. A sector shaped member K having upon it a Igeripheral flange K2, is hinged at a point 5, constituting the center of generation of its periphery, to a supporting stud K4 which depends from the upper part 'of the arm A8 of the appliance. The hinge K3 is 4conveniently situatedagainst the fulcrum end of the lever D, where the latter is provided with a reduced portion D2 adapted to connect to the member D3 carrying the fulcrum pins D2. The end of the aforesaid reduced portion D9 has a rounded face D1", adapted to'bear upon the end of a rod K5 disposed radially but somewhat to the side ofA the hinge K3, and having a screw threaded con- Anection with the flange K2, whereby initially it can be adjusted -endwise. B y means of this adjustment a line extending acro'ss the periphery of thevflange K2 can be brought to register with an index mark on a fixed part of the arm A3 when the lever D is restin' upon its stop D25 t will be seen that when upward movel ment of the plunger C takes place and the lever D-turns about its fulcrum pinsl D2, the reduced part D, at its end face D10, thrusts upon the rod K5, thus causing the sector K to turn on its hinge K3 and tobring a fresh part of the flange K2 opposite the index mark above mentioned. Such part of the flange may conveniently have inscribed upon it the words Load on. An aperture A5 in a cover A4' closing the end of the hollow arm A3 is provided opposite the flange K2 of the indicator so that the latters movements can be readily observed.

In use, the anvil. B4, by the aid of the height adjusting means, is brought to a position appropriate for the reception of the test-specimen upon it, and is then raised to bring the latter just in contact with the ball C2, and the'ball also in contact with the plunger C, if any clearance exists between them, the indicator above described giving warning if any -load is thereby applied Ythrou h raising the anvil too high. Theram and anvil B4 carrying the test-specimen are then raised by the power-driven mechanism Vabove described, and the ballcarrying plunger C is thereby raised from its position of rest, 'thus resiliently exerting its loading upon the ball C2 to 1ndent the test-specimen. As will be clearly seen the essential time element conditions are fulfilled in the predetermined manner, and, what is'of the utmost importance, are repeated in a similarmanner for every specimen tested.

It is to be understood that as the time allowed for attainment of the full load from zero, and the duration of its application have different' values according to the relative hardnessof the metal tested, interchangeable cams F3 of various contours may be employed to meet these conditions, or change speed gearing may be'employed to vary the speed of rotation of a standard typeof cam.

Where other indenting means as a cone` ended punch C are'desired in place of the. ball C2, the provisionfor the latter of the securing device in the form of the screw cap C5 with an aperture in its end part through which the active part of the indent.- ing device protrudes, enables the exchange to be readily effected.

Thus it will be seen that the invention provides means for carrying out tests in accordance with recognized standards with accuracy and in rapid succession, all the heavy work being performed by power. The man, ner of applying the load is in no way influenced by the weight or .size of the specimen, .and the construction described provides a simple, compact and self-contained appliance.

What I claim as myinvention and desire to secure by Letters Patent of the United States is 1. In a hardness testing machine, the combination of a support for the test-specimen, an indenting-'tooh and `means for causing the compression 0f the test-specimen between sai-d support and said indenting tool such that the attainment of full load upon the test-specimen at a` definite rate, the duration of application of full load, and the complete and rapid withdrawal of the load respectively, occupy predetermined intervals of time.

2. In a hardness testing appliance, a sup-- port for the test-specimen, an indenting tool,

lio

. port for the test-specimen, an indenting tool,

a load-applying member acting against a yyielding thrust of substantially constant value to cause the compression of the testspecimen between said support and said indenting tool; and a shaft rotating at uni- 1225` form speed and operatively'connected to the load-applying member in such manner that the attainment of full load upon the testspecimen at a definite rate, the duration of application of'full load, and the complete 180 and rapid withdrawal of the load respectively, 'occupy predetermined intervals of time.

4:. In a hardness testing appliance, a vertically movable support for the test-specimen, means for adjstin the vertical height of said support, a mem er carrying an indenting tool and locating same opposite said suppor-t, said memberbeing movable away from said support against a yielding 'thrust of a substantially constant magnitude, a shaft rotatin'g at a consta-nt speed; and an operative connection between said shaft and said vertically movable support whereby the latter is caused to thrust the test-specimen against the indenting tool carried by the yielding thrust member, in a predetermined interval l of time and at a definite rate of application of the load, to maintain it in that position for a further predetermined interval of time, and thereafter to permit the descent of the support and the -complete and rapid `Withdrawal of the test-.specimen from contact with the indenting tool.

5. The combination with a hardness test-` ing appliance as claimed in claim 4, of a stop limiting the movement of the-yielding thrust member toward the movable support for the test-specimen, and anV indicating device operatively connected to said yielding thrust member in such manner that 1t shows (a), when the yielding thrust is sustained maintenance of full load thereon, and its subsequent removal.

7. The combination with a hardness testing appliance as claimed in claim 2, of a plunger carrying the indenting tool, and a loaded lever acting on said plunger to thrust it toward the support for the test-specimen with a force of a substantially constant magnitude.

8. The combination with a hardness testing appliance as claimed in claim 2, of a plunger carrying the indenting tool, a lever acting on sald plunger to thrust it toward the support for the test-specimen, gear teeth formed on the free end of said lever lin an arc concentric with the lever fulcrum, a shaftcarrying a pinion engaging said gear teeth, a drum carried on said shaft and fast with said pinion, a cord attached to, and wound on said drum, and weights attached to said cord acting to vcause a downward thrust of the plunger aforesaid.

9. The combination with a hardness testing appliance, as claimed in claim 1, of a shaft rotating at constant speed, a cam, a sliding dog clutch onsaid shaft for actuating sa1d cam to operate the movable support for the test-specimen, for thrusting said testspecimen against the indenting tool, a spring acting on said dog clutch to disconnect rotationally said cam and said shaft, a second cam fast with the first cam and operatively connected to said dog clutch, said second cam having such contour and being connected tothe dog clutch, in such manner that once every revolution it ermits a movement of the dog clutch where y rotational disengagement of the two cams aforesaid from the constant speed shaft takes place; and controllable means operable at will, for actuating the dog clutch to connect rotationally said cams with the constantspeed shaft,

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

PERCY VENABLES VERNON.

lVitnesses:

H. F. HARRISON, G; T. HARRIS. 

